Emphasising in prevention of ACTUAL artificial harmful blue-light (HEV) from 420nm ~ 460nm generated from most electronic LCD/LED monitors, Not like other general/similar products described in the wavelength of 380nm~480nm with average ONLY! There are less critical harmful blue-light source can be found in 380nm ~ 400nm,

Light that is visible to the human eye is referred to as visible light and classified as in HEV (High Energy Visible Light) and LEV (Low Energy Visible Light). It comprised of the following colors: red, orange, yellow, green, blue, indigo, and violet.

However, invisible light, such as ultraviolet light is undetectable to human eye, that is why we have sunglasses protection to our vision. How about vision detectable blue-light (380nm ~ 460nm~500nm) & particularly artificial harmful blue-light (420nm ~ 460nm)?

Medical researches as early as 2001 had already determined continuous exposure to HEV blue-light (wavelength in the 380 – 480 range) will seriously damage our retina. Later years of 2013, 2014, 2015 & 2016 on medical, scientific, technology news have further identified and clearly stated the actual harmful blue-light wavelength range that could damage our vision is from 420nm ~ 460nm, ±10nm, in the visible color spectrum, which most likely can be found in our daily use LCD/LED screen display devices. This has been proved to be most harmful to the eyes because it has similar or even serious impact to our precious vision just like ultraviolet (UV) light (10nm ~ 380nm) does.

The interval of this wavelength exhibits colors between indigo (420nm) and blue (460nm), might able to causes artificial blue-light hazard on the retina.

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